【作者】 唐文忠；

【导师】 荚荣；

【作者基本信息】 安徽大学 ， 环境科学， 2007， 硕士

【摘要】 全世界每年大约生产8×10⁵吨的染料，其中80％是偶氮染料，10～15％的染料在生产和使用过程中被释放到环境中，造成严重的环境污染。白腐真菌依靠在次生代谢阶段产生的细胞外酶对多种难降解的有机污染物具有广普的降解能力，包括多种染料。白腐真菌对染料废水脱色方面的研究已经得到广泛的重视。本实验室选育的一株白腐真菌——裂褶菌F17可脱色降解多种不同结构的染料，具有很好的应用前景。本文研究了裂褶菌F17的生长特性及其对染料的脱色能力；研究了培养温度、初始pH、染料加入时间、染料初始浓度、诱导剂、天然物质、金属离子、抑制剂对染料脱色率的影响；新构建了一脱色降解体系，并在非灭菌条件下，研究了裂褶菌F17对染料的脱色降解能力；此外，分离并鉴定了偶氮染料刚果红的降解产物，初步推测了其可能的降解途径。实验结果如下：1、裂褶菌F17在马铃薯综合固体培养基中的生长速度明显快于限氮和麦芽汁固体培养基，最佳生长温度为28℃，生长pH范围在4.5～8.0之间；黄孢原毛平革菌和变色栓菌的最佳生长温度分别为37℃和28℃，生长pH范围均在4.5～6.0之间。2、裂褶菌F17、黄孢原毛平革菌和变色栓菌对染料刚果红都有一定的脱色能力。温度28℃、染料初始浓度100 mg·L^-1时，在限氮培养基中，脱色72小时后脱色率分别为66.9％、82.1％和81.9％。3、裂褶菌F17对染料刚果红脱色的最佳条件：温度28℃、初始pH值为4.5以及菌体摇瓶培养3天加入染料，刚果红初始浓度以100 mg·L^-1为宜，诱导因子藜芦醇、吐温80、土豆汁、松木屑的加入明显提高了刚果红的脱色率，其最佳终浓度分别为1.0 mmol·L^-1、0.1％、50 g·L^-1、3.0 g·L^-1，刚果红的最高脱色率在72小时后达到97.4％，而叠氮化钠和氰化钾的加入对刚果红的脱色有显著的抑制作用。4、裂褶菌F17在染料脱色体系中的最佳产酶条件：温度28℃、初始pH值为4.5以及菌体摇瓶培养3天加入染料，刚果红初始浓度以100 mg·L^-1为宜。另外，菌体产酶以MnP为主，最高酶活达到103.4 U·L^-1，LiP活力很小，未检测到Lac。刚果红的脱色率与累积MnP酶活具有良好的线性关系，相关系数为0.973。5、新构建了一脱色降解体系：0.1 mol·L^-1乳酸—乳酸钠缓冲液（pH=4.0）100 mL·L^-1，染料100 mg·L^-1，松木屑3.0 g·L^-1，湿菌球约70.0 g·L^-1。裂褶菌F17在此体系中对不同结构染料均表现出一定的脱色降解能力，其中刚果红和茜素红在脱色120小时后脱色率达90％以上，降解率达80％以上。在非灭菌条件下，裂褶菌F17在新构建的体系中也对染料表现出较高的脱色降解能力，脱色120小时后刚果红的脱色率达89.7％，降解率达78.6％。6、在新构建的体系中，裂褶菌F17对偶氮染料刚果红表现出较高的脱色能力，脱色192小时后刚果红脱色率为95.1％，而吸附率只有6.7％，表明染料的脱色主要是降解作用。对脱色96小时和192小时后的脱色液进行紫外—可见扫描，发现刚果红在可见光区495 nm处的吸收峰已消失，并在紫外区出现多个吸收峰。通过高效液相色谱分离得到一种刚果红降解产物，用质谱和傅立叶红外光谱鉴定，发现该产物分子量为184.2，主要官能团为—C₆H₄—和芳基—NH₂，结合刚果红结构和该产物的核磁共振波谱推测其为联苯胺，并且随着时间的延长，联苯胺逐渐被降解。更多还原

【Abstract】 The total annual world textile dye production is estimated at about 800,000 tons, among which azo dyes account for 80%. During processing, up to 10～15% of the used dyestuff are released into the process water, and generating serious pollution. White rot fungus are directly involved in the degradation of various xenobiotic compounds including dyes. The study on the treatment of dye effluents by White rot fungus already obtained the widespread value.The white-rot fungal strain--Schizophyllum sp. F17, which was isolated and stocked by our Lab., is effective to decolorize a wide range of structurally diverse synthetic dyes. This paper studied the growth and decolorization ability of Schizophyllum sp. F17, and the effect of culture temperature, original pH, the time of dye addition, original dye concentration, inducer, crudes, metal ions, inhibitor on the dye decolorization percentage. At the same time, a novel decolorization and degradation system was designed, and the test of dye decolorization by schizophyllum sp. F17 under non-sterile conditions was studied too. Moreover, a degradation product of Congo Red was separated and identified, and the degradation approach was speculated. The results showed:1. The growth rate of Schizophyllum sp. F17 in potato integration solid culture mediun was quicker than that in nutrient nitrogen limited and wort solid culture medium, and the optimum growth temperature was 28℃the range of growth pH was 4.5～8.0. The optimum growth temperature of Phanerochaete chrysosporium and Trametes versicolor were 37℃and 28℃respectively, the ranges of growth pH were all 4.5～6.0.2. Schizophyllum sp.F17, Phanerochaete chrysosporium and Trametes versicolor all had the ability to decolorize Congo Red. The decolorization percentage of Congo Red reached 66.9%, 82.1% and 81.9% respectively after 72h in nutrient nitrogen limited liquid culture medium, while temperature 28℃, original dye concentration 100mg·L^-1.3. The optimum conditions of Congo Red decolorization by Schizophyllum sp. F17 were as follows: temperature 28℃, initial pH 4.5, dyes added to the medium after 3 days of incubation in shaken flasks, and original dye concentration was 100mg·L^-1. The addition of veratryl alcohol, tween 80, potato extract and deal rag all had a great promotion on decolorization percentage, the maximum decolorization percentage of Congo Red reached 97.4% after 72h, but the addition of NaN₃ and KCN all had maked inhibition action on decolorization.4. The optimum conditions of enzyme production by Schizophyllum sp. F17 were as follows: temperature 28℃, initial pH 4.5, dyes added to the medium after 3 days of incubation in shaken flasks, and original dye concentration was 100mg·L^-1. The maximum activity of MnP, the main degradation enzyme, reached 103.4 U·L^-1, LiP activity was very low, and no laccase was detected. Moreover, there was a good linear relationship between percentage decolorization of Congo Red and cimulative MnP activity, and correlation coefficient was 0.973.5. A novel decolorization and degradation system was established: 0.1 mol·L^-1 lactic acid-sodium lactate buffer solution（pH=4.0） 100 mL·L^-1, dyes 100 mg·L^-1, deal rag 3.0 g·L^-1, wet mycelial pellets about 70.0 g·L^-1. Schizophyllum sp. F17 was effective to decolorize and degrade the tested dyes in the system, and the decolorization percentage of Congo Red and Alizarin Red all reached 90% upwards after 120h, the degradation percentage all reached 80% upwards. Schizophyllum sp. F17 was also effective to decolorize Congo Red in the system under non-sterile conditions, and the decolorization and degradation percentage reached 89.7 % and 78.6 % respectively after 120h.6. In the novel decolorization and degradation system, Schizophyllum sp. F17 was effective to decolorize and degrade Congo Red, and the decolorization and adsorption percentage reached 95.1% and 6.7% respectively after 192h. Therefore, it could be known that the decolorization of Congo Red by Schizophyllum sp. F17 in the system was achieved mainly by degradation. Furthermore, the UV-Vis spectrum of Congo Red reveals that the absorption peak at 495 nm vanished and some new absorption peaks appeared at ultraviolet region at both 96h and 192h of decolorization. A degradation product of Congo Red, molecular weight of 184.2 Da, was separated by HPLC. The MS and FTIR analyses demonstrate that the functional groups were-C₆H₄-and arylamine, suggesting that the degradation product was benzidine, which was confirmed by NMR, thereafter benzidine was degraded gradually with operational time.更多还原